There are many applications in which two parts, namely a stator and a rotor, which rotate against one another, are to be sealed non-hermetically against one another. Such an application is, for example, sealing of an annular gap between the stator and rotor of a hydraulic machine, a gas turbine in particular, with a gas flowing through the gap. Brush seals are known in the related art for non-hermetic sealing of annular gaps between two components rotating with respect to one another. For example, German Patent Document DE 199 62 316 C2, related to U.S. Pat. No. 6,695,314, both of which are incorporated by reference herein describes brush seals. Likewise, German Patent Document DE 100 18 273 A1, related to United States Patent Application Publication No. 2002/0020968, both of which are incorporated by reference herein, also describes brush seals.
In the above brush seals known from the related art, the brush seal is formed by several bristles wound around a core element and secured to the core element by a clamp ring. The unit composed of clamp ring, core element and bristles, which forms the actual brush seal, is situated in a bristle housing, which is formed by a support element designed as a support ring and a cover element designed as a cover ring.
Free ends of the bristles run against the sealing surface of the rotor or of the stator and thus seal the annular gap between the rotor and stator. The bristles of the brush seal may be oriented in the direction of rotation of the rotor to make soft, radial deflection of the bristles in contact with the rotor possible.
In the brush seals known from the related art, the support element, the cover element, and the unit composed of the clamp ring, core element, and bristles are made of metal. The metallic support elements and cover elements are typically designed as deep-drawn sheet metal or as turned parts. According to the related art, the metallic support element and the metallic cover element are usually connected by crimping to form the bristle housing. Brush seals made of metal are heavy in weight and relatively expensive to manufacture.